1. Field of the Invention
The present invention relates to digital optical cable communication systems; and, more particularly, to a two way burst mode optical cable communication system for use in optical communication and signal transmission between two optical nodes.
2. Description of the Prior Art
Many patents address issues related to optical communication between nodes in an optical high speed communication network. An Ethernet is a family of computer networking technologies for local area networks (LANs) commercially introduced in 1980. Standardized in IEEE 802.3, the Ethernet has largely replaced competing wired LAN technologies. Systems communicating over an Ethernet divide a stream of data into individual packets called frames. Each frame contains source and destination addresses and error-checking data, so that damaged data can be detected and re-transmitted. The standards define several wiring and signaling variants. The original 10BASE5 Ethernet used coaxial cable as a shared medium. Later the coaxial cables were replaced by twisted pair and fiber optic links in conjunction with hubs or switches. Data rates were periodically increased from the original 10 megabits per second, to 100 gigabits per second. Since its commercial release, the Ethernet has retained a good degree of compatibility. Features such as the 48-bit MAC (Media Access Controller which deals with the higher level issues of medium availability and a Physical Layer Interface) address and an Ethernet frame format have influenced other networking protocols. More recently, a Fast Ethernet is an extension of the existing Ethernet standard. It runs on UTP data or optical fiber cable and uses CSMA/CD (carrier sense multiple access with collision detection) in a star wired bus topology, similar to 10BASE-T where all cables are attached to a hub. It provides compatibility with existing 10BASE-T systems and thus enables plug-and-play upgrades from 10BASE-T. Fast Ethernet is sometimes referred to as 100BASE-X where X is a placeholder for the FX and TX variants. 100BASE-FX is a version of Fast Ethernet over optical fiber. It uses a 1300 nm near-infrared (NIR) light wavelength transmitted via two strands of optical fiber, one for receive (RX) and the other for transmit (TX) function. Maximum length is 400 meters (1,310 ft) for half-duplex connections and 2 kilometers (6,600 ft) for full-duplex over multi-mode optical fiber. Half duplex operation and CSMA/CD (carrier sense multiple access with collision detection) do not exist in 10 GbE. 100BASE-FX uses the same 4B5B encoding and NRZI line code that 100BASE-TX does. 100BASE-FX should use SC, ST, LC, MTRJ or MIC connectors with SC being the preferred option. 100BASE-FX is not compatible with 10BASE-FL, the 10 MBit/s version over optical fiber. 100BASE-SX is a version of Fast Ethernet over optical fiber. It uses two strands of multi-mode optical fiber for receive and transmit. It is a lower cost alternative to using 100BASE-FX, because it uses short wavelength optics, which are significantly less expensive than the long wavelength optics used in 100BASE-FX. 100BASE-SX can operate at distances up to 550 meters (1,800 ft). 100BASE-SX uses the same wavelength as 10BASE-FL, the 10 Mbit/s version over optical fiber. Unlike 100BASE-FX, this allows 100BASE-SX to be backwards-compatible with 10BASE-FL. Because of the shorter wavelength used (850 nm) and the shorter distance it can support, 100BASE-SX uses less expensive optical components (LEDs instead of lasers) which makes it an attractive option for those upgrading from 10BASE-FL and those who do not require long distances. 100BASE-BX is a version of Fast Ethernet over a single strand of optical fiber (unlike 100BASE-FX, which uses a pair of fibers). Single-mode fiber is used, along with a special multiplexer, which splits the signal into transmit and receive wavelengths. The two wavelengths used for transmit and receive is 1310/1550 nm. The terminals on each side of the fiber are not equal, as the one transmitting “downstream” (from the center of the network to the outside) uses the 1550 nm wavelength, and the one transmitting “upstream” uses the 1310 nm wavelength. Distances can be 10, 20 or 40 km 100BASE-LX10 is a version of Fast Ethernet over two single-mode optical fibers. It has a nominal reach of 10 km and a nominal wavelength of 1310 nm. It is described in IEEE 802.3-2005 Section 5 chapter 58.
U.S. Pat. No. 5,841,562 to Rangwala, et al. discloses a bidirectional modular optoelectronic transceiver assembly. This bidirectional modular optoelectronic transceiver assembly comprises a pair of interconnectable modules operating at the same wavelength. The transceiver comprises a transmitter module and a receiver-splitter module, which is plugged into a self-aligning socket of the transmitter module. The transmitter module includes a light source lensed to an opening in the socket, and the receiver-splitter module includes a ferrule, which is plugged into the socket. The ferrule carries an optical fiber so that one end of the fiber is optically coupled to the light source. This coupling enables an outgoing optical signal to be partially transmitted to a fiber pigtail located at the opposite end of the ferrule. A splitter is located at the other end of the fiber so that an incoming optical signal on the fiber pigtail is partially reflected to a light detector. There are no optical absorbers in the transceiver and noise from any stray coupling of transmitted signal and/or received signal cannot be avoided.
U.S. Pat. No. 6,592,272 to Masucci, et al. discloses burst mode transmission over multiple optical wavelengths. This method and system contemplates use of burst mode transmission on multiple optical wavelengths. In a passive optical network, a synchronization signal is transmitted from a central terminal to remote terminals, and burst data signals are transmitted from remote terminals to the central terminal. A first group of remote terminals transmits burst data signals in respective timeslots that are synchronized to the received synchronization signal and multiplexed at a first optical wavelength. A second group of remote terminals transmits burst data signals in respective timeslots that are synchronized to the received synchronization signal and multiplexed at a second optical wavelength. The timeslots are synchronized and phase aligned with each other such that optical crosstalk interference between adjacent optical wavelengths is avoided and each wavelength can be spectrally spaced as close as possible to adjacent wavelengths. This system uses multiple wavelengths and does not use a single wavelength for data communication between two transceivers using a single optical fiber.
U.S. Pat. No. 7,088,921 to Wood discloses a system for operating an Ethernet data network over a passive optical network access system. This data communications system provides multiple logical channels on a passive optical network (PON) using subcarrier multiple access (SCMA). A single PON shared bus is subdivided into several logical busses, so that each of a plurality of Ethernet Network Interface Cards (NICs) can communicate with the head-end on its own logical bus. The logical busses are configured so that the individual NICs can communicate with the head-end independently of each other, thereby assuring that collisions between NICs cannot take place. The PON includes multiple optical network units (ONU) which each communicate with a head-end over a logical channel. Collisions among upstream transmissions are thereby avoided and high speed Ethernet service over large distances is made possible. The network has many logical buses with each bus having its own Ethernet Network Interface Card, and does not connect two transceivers using a single optical fiber communicating data using a single frequency.
U.S. Pat. No. 7,283,753 to Giles, et al. discloses a system and method for WDM communication with interleaving of optical signals for efficient wavelength utilization. In this system and method of optical communication, optical signals are generated in multiple wavelength channels. Each optical signal is passively transported from an origination node of a network to a destination node. The destination node is determined by the signal wavelength. For at least some signals, the passive transport includes transport through a branch point of the network, such that the signal wavelength determines the output branch through which the signal is routed. The signals are generated according to a schedule devised to substantially prevent the concurrent arrival, at the same destination node, of signals having the same wavelength but coming from different origination nodes. This WDM system uses multiple frequencies for communication and does not use a single frequency for communication in a single fiber connected to two transceivers.
U.S. Pat. No. 7,590,109 to Beshai, et al. discloses data burst scheduling. A scheduling method and apparatus for transfer of data bursts in a network comprises electronic edge nodes interconnected by bufferless core nodes. Each edge node comprises a source node and a sink node, and each core node comprises several bufferless space switches operating in parallel. Each space switch has a master controller and one of the master controllers in a core node functions as a core-node controller. Each master controller has a burst scheduler for computing a schedule for transfer of data bursts, received from source nodes, to respective destination sink nodes. A core-node controller receives requests for bitrate allocations from source nodes and assigns each request to one of the master controllers of the core node. The scheduler determines schedules for concatenated reconfiguration periods. Alternatively, parallel schedulers determine schedules for overlapping reconfiguration periods. This system does not use a single optical fiber connecting two transceivers without additional burst period scheduling controllers.
U.S. Pat. No. 7,609,966 to Gumaste, et al. discloses a method and system for time-sharing transmission frequencies in an optical network. The optical communication system includes an optical ring, a hub node, and a plurality of local nodes. The hub node and the plurality of local nodes are coupled to the optical ring. The hub node is capable of receiving traffic over the optical ring from the plurality of local nodes on a transmitting wavelength and of transmitting traffic over the optical ring to the local nodes on a receiving wavelength. The plurality of local nodes are capable of adding traffic to and drop traffic from the optical ring and at least one local node is capable of adding traffic to the optical ring by determining whether any other local node is transmitting at the transmitting wavelength. The local node adding traffic is also capable of transmitting a request message to the hub node requesting use of the transmitting wavelength, in response to determining that no other local node is transmitting at the transmitting wavelength. Additionally, the local node adding traffic is further capable of receiving a grant message from the hub node and, in response to receiving the grant message from the hub node, transmitting traffic at the transmitting wavelength. In this system, the hub node allows the local node to transmit data only when no other node is transmitting in the optical ring network. This system does not use a single dedicated optical fiber connected to a pair of transceivers for communication between two nodes that are connected.
U.S. Pat. No. 7,626,916 to Kim, et al. discloses a method and system for crosstalk cancellation. Signals propagating in one communication channel can generate crosstalk interference in another communication channel. A crosstalk cancellation device can process the signals causing the crosstalk interference and generate a crosstalk cancellation signal that can compensate for the crosstalk when applied to the channel receiving crosstalk interference. The crosstalk cancellation device can include a model of the crosstalk effect that generates a signal emulating the actual crosstalk both in form and in timing. The crosstalk cancellation device can include a controller that monitors crosstalk-compensated communication signals and adjusts the model to enhance crosstalk cancellation performance. The crosstalk cancellation device can have a mode of self configuration or calibration in which defined test signals can be transmitted on the crosstalk-generating channel and the crosstalk-receiving channel. This system uses a compensator to remove the crosstalk and does not use a single fiber without additional hardware.
U.S. Pat. No. 7,751,712 to Zhao, et al. discloses passive optical network and data communication method thereof. This Passive Optical Network includes: an Optical Line Terminal, an Optical Distribution Network, and an Optical Network Unit or an Optical Network Terminal, wherein the Optical Line Terminal is adapted to exchange data with the Optical Network Unit or the Optical Network Terminal by using an optical module via the Optical Distribution Network. The optical module is an optical module sending data in a continuous mode. Further, a method for data communication based on the Passive Optical Network includes: sending data by using an optical module sending data in a continuous mode; receiving the data by an optical module based on a set optical power threshold of data “0” and a set optical power threshold of data “1”. The data is not transferred through the optical fiber in the burst mode but by adjusting the power of a single frequency continuous optical signal.
U.S. Pat. No. 7,917,036 to Ori, et al. discloses bi-directional optical module. This optical transceiver includes a bi-directional optical subassembly with a printed circuit board which transmits and receives light for the bi-directional optical subassembly and an outer casing which covers the bi-directional optical subassembly and the printed circuit board. The bi-directional optical subassembly includes: a laser diode; a photodiode; a stem on which to laser diode and the photo diode are mounted; a cap, which cooperates with the stern to seal the laser diode and the photodiode; and a crosstalk reducing structure for reducing optical and/or electric crosstalk. The crosstalk reducing structure may include a layer, which is formed on an inner surface of the cap and is able to absorb an infrared ray. The crosstalk reducing structure includes a block, which is disposed between the laser diode and the photodiode, and is able to physically prevent stray light from traveling from the laser diode to the photodiode. The single fiber operates in WDM system wherein a single mode optical fiber is used for transmitting and receiving on different wavelengths, 1310 nm and 1490 nm and does not use a common wavelength for communication.
US Patent Application 20030113118 to Bartur discloses a smart single fiber optic transceiver. This fiber optic transceiver is adapted for use in an optical fiber data transmission system and is capable of detecting fiber connection problems and providing visual or other indications of a problem. The fiber optic transceiver contains a fiber interface, a receiver, a transmitter, and a microcontroller. The microcontroller controls the transmitter to modulate the laser power to transmit test data and the transceiver includes circuitry and microcode to detect fiber connection problems, including reflection and cross connections. This enables trouble shooting during installation and/or reconfiguring the connection automatically, in response to a connection problem, and provides a physical layer link. This transceiver system uses a microcontroller coupled to the transmitter and receiver and providing a modulated power control signal to the laser driver during a test mode to transmit test data and monitoring received signals to detect connection problems.
There remains a need in the art for a optical communication high speed communication that uses a single fiber using transceiver on both ends of the optical fiber communicating using a single wavelength without adding preamble and delimiter information thereby providing faster more efficient communication in a high speed network.